Improvement in petroleufvl-stills



ZSheets--Sheet 2., l. L. STEWART.

\ Petroleum-Still, 910,162,965; Patented May 4,1875.

THE GRAPHIC BKLPHOTO :LITE-39 L41 PARK PLACE, NAV.

JOHN L. STEYVART, OF PHILADELPHIA, PENNSYLVANIA.

IMPROVEMENT IN PETROLEUM-STlLLS:

Specification forming part of Letters Patent No. l62,965, dated May 4, 1875; application tiled August 8, 1874.

To all whom t6 may concern:

Be it known that I, J oHN L. STEWART, of Philadelphia, State of Pennsylvania, have invented a Petroleum-Still, of which the following is a specification:

My invention relates to improvementsin therein, and make oil ot' a different specific gravity from each compartment. These compartments are provided with scrapers secured to endless chains, which are mounted on shafts driven by power. These sera-pers remove all sediment and parafne oil from the bottoni ot' each compartment, into a receptacle at the back end, thereby obviating the necessity of having to stop to clean out the stills. Overflow -pipes are so arranged in combination with self-acting valves controlled by floats, as to carry oft' the heavy oil from the bottom of one still into the next contiguous still, and thereby maintain constantlythe proper level of oil in each'compartment.

My invention consists in the combination, with a compartment-still for continuous distillation, of communicating pipes and automatic regulating-valves, whereby the oil in each still is maintained at a proper level; also, in the combination, with a compartmentstill for continuous distillation, of a pipe or trough conveying the oil from the rear pocket of one still to the front end ot the next still; also4 in making the said pipe as a conduit or lining along the side of the still, to form a lining` ot'running oil between each compartment, and thereby prevent the temperature of one compartment being affected to any great extent by that ot' the next; also, in the combination, iu a compartment-still for continuous distillation, ot' scrapers arranged on endless chains; also, in the particular' construction of the scrapers, and the inode ot' connecting them to the chain; and, also, the general combination of parts which goto form the continuous scraping arrangement.

Figure lis a longitudinal section through the still. Fig. 2 is a plan. Fig. 3 is an end view ofthe interior. Figs. 4 and 5 show details of the chain-drum and scrapers slightly modified. Fig. 6 shows the face ot' the butterfly-valve.

A B are the compartments ot' the still, separated from each other by the dividing-plate C riveted water-tight. These two compartments, or it may be three, four, or tive of them, are set in brick-work. rlhe bottom of each inclines downward toward the rear end and terminates in a funnel-shaped receptacle, D, which has an outlet, d1, at the bottom, above which is litted a valve, dz, through which the tar and refuse are discharged whenever it may be desirable. The heavy oil passes from lthe bottom of thereceptacle D of compartment B, through the pipe E1, into compartment A. At the outlet ot pipe E1 is a butterliy-valve, h, the face of which is seen in lfig. 6. The outlet from each ot these pipes is about six inches lower than the level of the oil in the compartment fromwhich it takes its supply. This difference of level tends to produce a current through the compartments from the first toward the iinal still where the tar is discharged. It also serves to overcome any slight difference of pressure in each still, due to unequal iiring. The level of the oil in each still is regulated by a iioat, G, operating the butterily-valve la. The oil as it passes from this pipe El iiows into the trough K, and thence to the front of the still, Where it mixes with the main body ot the oil in the compartment A, through the opening k1, at or near the top of the-trough; A pipe will answer to convey the oil to the front of the still when the stills are separate, but the trough K answers better in a compartment-still, as a lining between one compartment and the neXt.

I will now describe the plan for scraping the bottomof the still.

M N are grooved pulleys mounted on shafts m1 nl. The shaft inl4 passes through all the compartments to the`ou tside of the still, and is turned by power. The shaft u1 turns in sliding bearings at each end, so that the 'tension of the chain P can be adjusted by the screws 191191, which pass out ofthe front of the still. To the chain P are hinged the hooked scrapers S upon cross-bars R1, by means of rods R2.

These Scrapers have a T-shaped end, which is placed at such a distance from the bars R1, as to permit of a small motion, and allow the Scrapers, by their own weight, to accommodate themselves to the bottom of the Still. In Figs. 4 and 5 these details are shown enlarged and modified. The chain P is made curved, to iit the pulley N, which is made with projectingpins n2. r1 are the cross-bars; r2, the rods; S, the Scrapers with removable ends of chilled iron SZ. Any of the usual chains and pulleys used for this purpose may be employ ed, provided the bar r1 can be secured upon the chain. By turning the shaft m1 the Scrapers traverse the bottom of the still and remove all the sediment into the funnelshaped end D, from whence it and the heaviest of the oil is withdrawn through the pipe E.

I will now describe the operation of my improved process of distillation: First, the benzine can be removed from the crude oil before entering the iirst compartment, or it can be used in the crude state direct from the tanks, the depth ofthe oil in each compartment being regulated by a oat and butteriy valve. When run by ordinary crude oil the rst compartmentB is heated sufficiently to remove all the benzine. The heavier oil, settlin g to the bottom of the funnel-Shaped receptacle at the back end, is conducted, by pipe E', into trough K in the adjoining compartment, which trough conducts the oil to the surface ofthe forward end of the same. This compartment is heated sufficiently to distill the lightest portion of what is termed the burning-oil. The heavier product, again deposited in the pocket, as above, is removed in like manner to the surface of the third compartment, which is heated to the proper temperature to distill the heavier portions of the burning-oil; The heavier parafline-oil and sediment are in like manner deposited, and removed in the same way to the fourth compartment, which is heated to the high temperature necessary to crack the heavy oils, or, more properly speaking, it is subjected here to a destructive distillation, so that the oil distilled over, is lighter in gravity on account of the portion of carbon deposited in the still. This carbon, in the torm of tar, iS scraped into the receptacle and drawn off at pleasure. Destructive distillation is only carried on in the last compartment, into which the heavy oil and refuse are finally deposited. These Separationscan be increased to any number by increasing the number of compartments.

It is Well known to refiners of petroleum that unless the heavy oil contained in crude petroleum undergoes this destructive distillation, it will not burn properlv in lamps, as the capillary attraction will not carry it up the wick. Neither will itmake what is termed a standard White oil.

As the destructive distillation requires a certain temperature, itis evident that continuous distillation cannot be carried on successfully in a single still, as the lighter-gravity oils Whichvare continually fed in distill at a comparatively low temperature, and their vapors carry over the heavy oils mechanically, as is proved by the temperature to run Such a still being too low to break the heavy oil. Each of the compartments to my Stills is Worked independently of the other, excepting the feeding of the heavy oils from one to the other. As the compartments are run by separate lires, each can be heated to any desired temperature. The oil, as it passes along the trough K from pipe E,serves as alinin g between the two compartments, protecting in a large degree the temperature of one compartmeutfrom being affected by the temperature of the other.

By this plan of passingthe heaviest oil from receptacle D of one section, B, of the still, into the next section, A, and so on to thelast compartment in which destructive distillation only takes place, the level of the oil being automatically regulated by a iioat and valve, and provision being made for removing the coke and Sediment from the bottom of the last still, I am able to keep the still in continuous operation and distill a different grade of oil from each compartment.

What I claim isl. In a series of stills operating in conjunction for the continuous distillation of petroleum into products of various Specific gravities, the combination of the said Stills A B, the overflow-pipes E E, and the automatic regulating-valves h, substantially as herein described.

2. In a series of stills operating in conjunction for the continuous distillation of petroleum into products of various Specific gravities, the combination of the said stills A B, the overliow-pipes E E, the automatic regulating-valves h, andA Scrapers upon endless chains, substantially as herein described.

3. The combination of the Scrapers S, the rods r2, the cross bars r1, and the chain P operating in a petroleum-still, as herein described.

4. The combination of the endless chain I), and the L-shaped Scrapers S hinged and having a limited movement upon the chain, substantially as herein described. A

5. The L-shaped scraper S hinged and having a limited movement, as and for the purpose described, in combination with the chilled-iron points S.

6. In a compartment, A, operating with others for the continuous distillation of petroleum, the combination of the trough K conveying the overflow from the pipe E', and discharging it upon the surface of the oil at the front of the still, as herein described.

JOHN L. STEWART. Witnesses: I

EDWD. BROWN, N. H. JARA/rau. 

